Belting and process of making the same.



W. H. BRADSHAW.

ELTiNG AND PROCESS oF MAKING THE SAME.

APPLICATION FILED SEPT. 5.1916-,

.Patented July 31, 1917.

WILLIAM H. BRADSHAW, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR 'I'O WILLIAM THOMPSON PLUMMER, 0F PHILADELPHIA, PENNSYLVANIA.

BELTING AND PROCESS OF MAKING THE SAME.

Speccaton of Letters Patent.

Patented July 3i 1917.

Application ledSeptember 5, 1916. Serial No. 118,456.

` To all -ulwm it ymay concern.'

Be it known that l, WILLIAM: H. BRAD- snxw, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia` and State of Pennsylvania, have invented certain new and useful Improvements in Belting and Processes of Making the Same, of which the following is a specification.

This invention relates to belts or belting and a process of making the same.

One of the objects of the present invention is to produce a simple and practically constructed belt having great durability. A further object is to produce a belt which will not be affected by heat arising from excessive slipping. A further object is to produce a belt which will be substantially proof againstthe'action of oil, water, steam, gases, acids and the like, and which can be stored for years in a warm place or subjected to direct sunlight without deterioriating. A further object is to produce a belt which is sufficiently flexible to hug the vface of a pulley of Vrelatively small diameter and which will be substantially non-stretchable when transmitting an overload. A further object is to produce a belt which has a high coefficient of friction. A further object is to produce a belt which can be made endless by properly scarling the ends and then cel inenting them together. A further object is to provide a process whereby such a belt canI be made which will be relatively inexpensive.

Other objects will be in part obvious from the annexed drawings and in part indicated, in connection therewith, by the following analysis of this invention.

This invention accordingly consists in the combined features of construction, the unique relation of the parts and in the'r'elative proportioning and disposition thereof, as well as the several steps of the process and their relation to the other steps, all as more completely outlined herein.

To enable others skilled in the art so fully to comprehend the underlying features such drawings like characters of reference denote corresponding parts throughout all views, in whichy Figure l is a diagrammatic view, illustrating one of the various ways in which the belt can be made; and

Fig. 2 sectionally a. portion of the belt.A

As conducive to a clearer understanding of the invention, it may be stated that it deals more particularly .with the manufacture of that type of belting generally referred to as multi-ply belts, that is, belts made of a pluality of plies of fabric, or the like, superimposed in a direction perpendicular to the plane of the belt. These belts are adapted not only forthe transmission of power through the medium of pulleys,but also for use as conveyer and elevator belts. It is highly desirable that belts of this character be strong, durable, flexible, nonstretchable, and substantially fluid and heat proof, and at the same time, possess a high coefficient of friction upon the traction or pulley surface, in order to obtain the maximum efficiency in the transmission of power. I have found that a multi-ply fabric belt, the plies of which are suitably treated and cemented together with a cement, the essential ingredient of which is preferably a cellulose est-er, for example, nitrocellulose, cellulose acetate, etc., and the driving face of which is treated with a suitable materia-l to provide a driving surface, preferably with balata, produces a highly efficient and desirable belt and fulfils all these requirements. Itis such a. belt and a process for manufacturing the same substantially as hereinafter outlined, to which the present invention is especially directed.

lt may have been attempt-ed to treatthe various plies-of a multi-ply belt With a nitrocellulose solution by the impregnation y i tive stiffness and tendency to stretch of the ley, .for example, there was a tendency for is a diagrammatic view, 'showing y the nitrocellulose to craclr and dalle ed and thus eliminate or minimize results and advantages sought to be accomplished thereby.

lt is believed that the pres-ent invention overcomes these and other'objections by the peculiar steps, or combination of steps, including more specifically the sizing of the plies with cement and drying the sizing While the plies vare under tension, and cementing and pressing together the various plies of the fabric While under tension. Sizing theplies and drying the sizing while the fabric is under tension serves several purposes, such as, to eliminate the stretch and to prepare the surface for future cementing. Alf the belt stretches after it is cemented together, the integrity of the cement is broken and it flakes ed, allowing the plies to separate. By stretching the lies and thenfcernenting them, or by sizing each ply, drying the sizing While the ply is under tension, and then cementing them, it is possible' to eliminate the excesivo stretch and so produce a flexible belt the plies of which will not separate. rlhe outer surface 'of oneor' both of the outer or en terior plies is preferably treated to increase the coecient of friction, one of the outer plies may be treated to prevent injury to the belt b Water, oil, acid or the like, according to t e use to which the belt is put.

Referrin now to Fig. 1 of the drawings,

in `which t ere is diagrammatically shown oneof the various vvays of carrying out the present process, 5, 6, 7 and 8 denote the several rolls or plies of fabric, in the present case four in number, although it is, of course, to be understood that more or less plies -rnay be used, as desired. 'lhese several plies are uni-round from the respective rolls,andv are nally Wound upon the iinishing roll 10 under tension. Separate braking devices 11 are preferably provided adjacent the ply rolls to rovide uniform tension. rlhe several plies t en pass through calendering rolls'12 Where the relatively soft bers are ironed down smooth and dat before thesurfaces of the plies are treated or sized with the nitrocellulose; solution,

thereby providing a plane surface to `which to apply the cement. 'lhe solution or cement which l prefer to use for sizingthe plies and subsequently cementing them together isfniade by dissolving celluloid scrap in a solvent containing 10% amylacetate,

'20% acetone, 35% Wood alcohol, and 35% benzol. rl'he proportion of solvent to scrap depends uponv the texture of the fabric used. 'lhe upper fabric or ply 5 is preferably sized on both sides, thereby coating What will later be the baclr of the belt inorder to render it duid proof, While the lnnttorn ply is coated on the top side only, as shown by the coating ineens 1t, leaving the under sido clear to be treated subsequently, es will be retener ,coated plies are then led through a suitable drying apparatus 15 While under tension. The amount of tension required de pends upon the type of fabric used. lt has been found that good results are obtained bythe use of a tension of 20 lbs. per inch yof Width of single ply when the fabric used is a l() ounce cotton duck. To make belts for general machine shop use, a 10 ounce cotton duck having a reasonably tight Weave is preferably used. The plies then are led past feed rollers 16, when the plies 6 and 7 are again coated on both sides by coating means 17 of any desired type. The top ply 5 is coated on the under or adjacent side only. rllhe bottom ply 8 is at this point 18 treated with a solution or material to increase the coedicient of friction, preferably vvith balata, in combination with other materials or by itself, vvhich not only coats but impregnates entirely through the ply to the coating of cement applied toits top side by the device 14C and as shovvndiagrammatically in Fig. 2.` 'lhis ply is then dried by any suitable drier 2G and passed through a coating device 21 for coating the vtop surface only with cement. All of the plies then pass over suitable feed rollers 22, during which time the solvent has an opportunity to evaporate partially from the cement, and vthen through pressing rollers 23 Where the several plies are securely united before the cement has completely dried. 'lhe plies being under tension will be held in their tensioned position as they are Wound uponthe final nishing roll 10.

"While the present particularly with a` belt made of separate plies, it is to be understood that it may beV disclosure deals more made from a single sheet of fabric folded back and forth upon itself in a Well known manner, and the cement applied thereto in stri s by any suitable coating device adapted or that purpose. From the above, it vvill be seen that the present. invention is directed to a, simple and practical belt and the process of manufactuiung the same,possessmg among others,

lid

all of the desirable qualities and advantages herein set forth.

Without further analysis, the foregoing will so fully reveal the gist of this inven# tion that others can by applying current lmovvledge readily-adapt it for various ap-4 plications Without omitting certain features What I claim is 1. A belt made of a plurality of plies cemented together With a cement the essential ingredient of which is a cellulose ester, one of the outer plies having all but. its inner surface free from said cement but impregnated with a suitable material to provide a driving surface for the belt.

2. A belt made of a plurality of approximately non-stretchable plies, 'cemented together with a cement, the essential ingredient of which is a cellulose ester,.one of the outer plies having all buty itsv inner surface free from said cement but impregnated Witha suit-able material to provide a driving surface for the belt. l

3. A belt made of 'a plurality of plies cemented together with a cement', the essential ingredient of Which is nitrocellulose, one of the outer plies having all but its inner surface free from said cement but impregnated with a suitable material to provide a driving surface for the belt. i

4. A belt made of a plurality of plies sized under tension and cemented together with a cement, the essential ingredient of which is a cellulose ester, one of the outer plies having all but its inner surface free from saidcement but impregnated with a suitable ma-v terial to provide a driving surface for the belt. n

5. A belt made of a plurality of approximately non-stretchable plies, cemented together with a cement, the essential ingredient of which is a cellulose ester.

6. A belt made of a plurality of plies cemented together with a cement the essential ingredient of which is a `cellulose ester, one of the outer plies having all but its inner surface free from said cement but impregnated with balata.

7. The method of making multi-ply belts which consists of the steps of properly stretching the plieslongitudinally and ceinenting them together With a cement, the essential ingredient of which yis a cellulose ester.

s. The method of making belts whiehwnlof which is a cellulose ester, drying said sizing while the plies are under tension' and securing the several plies together.

9. The method of making belts which consists in the steps of calendering a plurality of plies of fabric, sizing the calendered surfaces with a cement, the essential ingredient of which is a cellulose ester, drying said sizing while the plies are under tension and cementing the several plies together with such a cement. p

10. The method of making multi-ply belts which consists of the steps of stretching the plies longitudinally, cementing them together with a cement, the essential ingredient of. which is a cellulose ester, and iinpregnating the outer Jface of yone of the outer plies with a suitable material to provide a drivin surface for the belt.

11. he method of making belts which consists of the steps of calendering a plurality of plies of fabric, sizing the adjacent calendered surfaces With a cement the essential ingredient of which is nitrocellulose, drying said sizing whlethe-plies are under tension, impregnating the outer I'ace of one p of the outer plies With balata and cementing the plies together with a nitrocellulose cement.

' l2.v The method of making multi-ply belts which consists of the steps of preliminarily stretchingl the plies of the belt to remove the stretch as much as possible and cement- `ing saidv plies together with a substantially non-elastic cement, the essential ingredient of which is a cellulose ester.

In testimony whereof I ailix my signature i in the presence of two witnesses.

WILLIAM I-I. BRADSHAW.

Witnesses:

Jnssm E. LEA,

GARET T. BnnnN. 

